Phonograph recorder and reproducer



(No Model.)

. T. A. EDISON. IF PHONOGRAPH RECORDER AND REPRODUGER.

No. 397,280. Patented Feb. 5, 1889.

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NITE STATES PATENT OrTIcE.

THOMAS A. EDISON, OF LI.E\VELLYN PARK, NE JERSEY.

PHONOGRAPH RECORDER AND REPRODUCER.

SPECIFICATION forming part of Letters Patent No. 397,280, dated February 5, 1889.

Application filed September 27, 1888- Serial No. 286,552. (No model.)

To aZZ whom it may concern Be it known that I, THOnAs A. EDIsON, of Llewellyn Park, in the county of Essex and State of New Jersey, have invented a certain new and useful Improvement in Phonograph s, (Case No. 80%) of which the following is a specification.

My invention relates to the recording and reproducing devices of the phonograph; and

my object is to enable such devices to work independently of irregularities in the surface of the phonogram. Sometimes in the manufacture of phonogram-cylinders irregularities or eccentricities occur in the formation of the surface, and sometimes the cylinders become warped after manufacture, and if provision is not made to prevent it such irregularities will occasion oscillations of the reproducingpoint and the diaphragm, which will interfere with the recording or reproducing of the sound. This is obviated by my invention, which consists, mainly, in so supporting the recording or the reproducing point that it is capable of movement independently of the diaphragm, but that such independent movement is retarded so that it does not occur with the rapid and minute vibrations of the sound-record, but only with the slower and more extensive vibrations which are produced by irregularities in the shape of the phonogram. The sound- *ibrations have to-and-fro movements of great rapidity and large number per second, and these cannot move the retardin g device, so that the same acts as though it were fixed, and all the energy due to the sound-waves or the sound-record is communicated directly from the diaphragm to the recording-point or from the reproducing-point to the diaphragm, while the movements given to such points by eccentricities of the phonogram, being long and slow, overcome the tendency to inaction of the retarding device, and so permit the movement independent of the diaphragm. This makes it possible to record on or reproduce from a very irregular revolving phonogranr even one which is oval in shape.

In carrying my invention into effect I-support the recording or reproducing point pivotally, and I attach to such point a retarding device, which is preferably a fan or piston, the inertia and retardation of which retarding device are such that it will not be moved by the sound-vibrations, but will be moved by the slower movements referred to, so that the latter are not communicated to the diaphragm; but under the quick sound-vibrations the connection of the reproducing-point to the diaphragm is practically a rigid one. Instead of a fan I may employ a weight, preferably in the form of a wheel; but the fan or piston is found to be preferable.

My invention is illustrated in the accompanying drawings.

Figures 1 to 6 illustrate repioducers. Fig. 1 is a cross-section of the ear-piece and side view of the reproducing-point and the devices connected therewith; Fig. 2, a top view of the reproducing-point and the retarding device; Fig. 3, a perspective view of the same. Fig. 4 shows a modified arrangement of the retarding device; Fig. 5, a different mode of pivoting the reproducing-point and Fig. 6 illustrates the use of a wheel as a retarding device. Figs. 7 and 8 show recorders. Fig.7 is a cross-section of the mouth-piece and side View of the recording-point and retarding device, and Fig.8 shows in section another form of retarding device.

Referring first to Figs. 1 to 6, A represents the diaphragm, and B a portion of the surface of the cylinder containing the soundrecord. A small cork, a, is attached to the center of the diaphragm, and from the cork project small lugs b, on which the reproducing-point c is pivoted. Lugs I) extend from a plate which is secured to the end of the cork a by suitable ce1nentsueh as melted shellac--a11d the cork itself is similarly cemented to the diaphragm. A fine spring, (I, is eemented in a slit in the cork and bears upon the reproducing-point, so as to hold the same against the phonogram. The arm which terminates in the reproducing-pomt extends back 7 past the pivot, and has soldered to it at 6 two prongs of thin metal, f, to which is attached a piece of thin mica, g, which preferably has side ribs, so as to form a trough. This forms a fan or vane, and I have found that such a retarding device is practically rigid under the minute vibrations due to the sound-record, so that such vibrations are communicated di rectly through the cork a to the diaphragm; but when the reproducing-point passes over any serious irregularity in the surface, such as would injure the reproduction of sound, the slow movement thus produced overcomes the inertia of the fan, and the reproducinglever rocks on its pivot, being kept pressed against the surface by the spring, so that such an irregularity is taken up by the reproduei n g arm itself and does not connnunicate motion to the. diaphragm. The pressure of the sprin is very light and merely coiu'lterbalances the weight of the fan,so as to overcome any tendcncy of the point to leave the surt'face. It: will be seen that I connect the spring with the diaphragm. I do this to prevent any loss olf motion through the sprin If it were connected to the rim, any movement or energy which might be comnumicated to it would pass to the rim and be lost; but where the spring is joined to the diaphragm any motion communicated to it: is given to the diaphragm and aids the am 'ilitl'ide of vibration.

In the form shown in Fig. -l: I inelose the [an in a chamber, 71, secured to the arm of the diaphragm, so as to increase the resistance to the motion of the fan.

In Fig. the reproduclng-lever ivoted at its outer end to the cork on the diaphragm, and the spring projects from said cork and lies upon said lever.

In the form shown in Fig. (l a small wheel, 1', is supported in bearings below the rim of the diaphragm, and a link-connection is made at In between the reproducing-lever and the shaft of said wheel. In this case the weight of the wheel retards the movement of the lever on its pivot under the sound-viln'ations in the same way as the tan in the other form; but: under the slow motions of the irregularities in the cylinder the weight ot the wheel is overcome, so that it turns and allows the lever to rock on its pivot. Any of these forms may be readily applied to recorders.

Fig. 7 shows an arrangement precisely like that of Fig. 5, r being the recording-point.

I? i 3 shows a d i llj'erent arrangement, which is also applicable to reproducers. A small hollow cylinder or dash-pot, s, is attached to the center of the diaphragm, and in this works a plunger or piston, t, attached to lever 11, which carries the recording-point r. The lever '11 is pivoted below the rim of the mouthpiece, and the fine spring attached at the center of the diaphragm bears at the free end ol:' said lever. The rapid and minute sound-vibrations do not move the dash-pot upon the piston, (or vice versa in a reprodueerg) but slow movements due to irregularities move the piston and so cause the desired movement of the point indepemlent ot' the diaphragm.

It will be seen that in all these instances a retarding device is used whose in ertiais such as will, not be overcome by the normal quick motion of the recording or reproducing point but will permit it to move under the slower motions due to defects in the eylimler-surface.

\Vhat I claim is 1. In a recorder or reproducer for phonographs, the con'ibination, with the diaphragm, of the recording or re n-oducing point connected therewith and capable of a retarded movement independent of the movement of the diaphragm, substantially as set forth.

2. In a recorder or reproducer l'or phonographs, the combination, with the diaphragm, of the recording tor reynroducing point connected. with said diaphragm and capable olf movement independent thereof, and provided with a ret'z'n'ding device for controlling such im'lcpendent movement, substantially as set forth 23. In a recorder or reproducer [for phonographs, the combination, with the diaphragm, ol the rounding or reprmlucing point pivotally connected therewith, so as to have a movement independent thereof, and provid ed with a retarding device controlling such movement, substantially as set forth.

4-. In a recorder or reprodueer for phonographs, the combination, with the diaphragm, of the recording or reproducing point connected therewith and capable of a retarded movement independent of the diaphragm, and a spring for holding said point against the sound-record, substantially as set forth.

5. In a recorder or reproducer for phono graphs, the combination, with the diaphragm, of the recording or reproducing point connected therewith and capable of a retarded movement; ind cpen den t of the diaphragm, and a sprin ctmnected with said diaphragm for holding said point against the soruul-reco1vl, substantially as set forth.

6. In a recorder or rcproducer for phonographs, the combination, with the diaphragm, of the recording or reproducing point pivotally connectedtherewith, a spring for holding said point against the sound-record, and a retard n device for controlling the movement: of said point on its pivot, substantially as set forth.

7. In a recorder or reln'tnlucei. for phonographs, the combination, with the diaphragm, of the recording or reproducing point pivotally connected therewith, a spring connected with the diaphragm for holding said point against the soinid-record, anda retarding de vice for controlling the movement of said point on its pivot, substantially as set forth.

8. In a recorder or reproducer for ph0nographs, the combination, with the diaphragm, of a lever pivoted upon said diaphragm so as to have a movement independent thereof, and carrying the recording or reproducin g point, and a retarding device connected with said lever, substantially set forth.

9. In a recorder or rcprodueer for phonographs, the combination, with the diaphragm, of a lever pivoted thereto and carrying the recording or reproducing point, and a fan attached to said lever, substantially as set forth.

10. In arecorder or reproduccr for phonographs, the GOllllJlllfltlOll, with the diaphragm,

of the recording or reproducing point connected with said diaphragm and capable of movement independent thereof, and a fan or equivalent device for retarding such movement, substantially as set forth.

11. In a recorder or reprodncer for phonographs, the combination, with the diaphragm, of a lever pivoted thereto and carrying the recording (ii-reproducing point, a fan attached to said lever, and a spring [or holding said 10 point against the sound-record, substantially as set forth.

This specification signed and witnessed this 19th day of September, 1888.

'lllOS. A. EDISON. \Vitncsses:

WILLIAM PELZER, A. W. KIDDLE. 

